MgraInteractive
This program uses the capabilities of AIL's interactive graphics and extracts the blobs within a user defined region.
Language: C++
Functions used: MappAlloc, MappFree, MblobAlloc, MblobAllocResult, MblobCalculate, MblobControl, MblobDraw, MblobFree, MblobGetResult, MbufAlloc2d, MbufFree, MbufInquire, MbufRestore, MbufSetRegion, MdispAlloc, MdispControl, MdispFree, MdispSelect, MgraAlloc, MgraAllocList, MgraControl, MgraControlList, MgraFree, MgraGetHookInfo, MgraHookFunction, MgraInquireList, MgraRectAngle, MgraText, MimBinarize, MsysAlloc, MsysFree
Categories: Overview, General, Industries, Machining, Applications, Finding/Locating, Counting, Modules, Buffer, Display, Graphics, Image Processing, Blob Analysis, What's New, Older
///////////////////////////////////////////////////////////////////////////////
// Aurora Imaging Library
// Filename: MGraInteractive.cpp
//
// Description: This program uses the capabilities of AIL's interactive
// graphics, along with the Blob analysis module, to count
// objects within a user-defined region.
//
// (C) 1992-2026 Zebra Technologies Corp. and/or its affiliates
// All Rights Reserved
///////////////////////////////////////////////////////////////////////////////
#include <AIL.h>
// Data structure to handle parameters for the hook function.
struct STestParameters
{
AIL_ID AilDisplay,
AilGraphicsList,
AilGraphicsContext,
AilBinImage,
AilBlobContext,
AilBlobResult;
AIL_INT RegionLabel;
};
// Example function declarations.
void InteractivityExample(AIL_ID AilSystem, AIL_ID AilDisplay);
AIL_INT MFTYPE HookHandler(AIL_INT HookType, AIL_ID EventId, void* UserData);
void CountObjects(AIL_ID AilDisplay, AIL_ID AilGraphicsList,
AIL_ID AilGraphicsContext, AIL_ID AilBinImage,
AIL_ID AilBlobContext, AIL_ID AilBlobResult);
//*****************************************************************************
// Main.
//*****************************************************************************
int MosMain(void)
{
AIL_ID AilApplication, // Application identifier.
AilSystem, // System Identifier.
AilDisplay; // Display identifier.
// Allocate defaults.
MappAllocDefault(M_DEFAULT, &AilApplication, &AilSystem, &AilDisplay,
M_NULL, M_NULL);
// Print example name.
MosPrintf(AIL_TEXT("\nINTERACTIVE REGIONS AND SUBPIXEL ANNOTATIONS:\n"));
MosPrintf(AIL_TEXT("---------------------------------------------\n\n"));
MosPrintf(AIL_TEXT("This program determines the number of blobs in a region\n"));
MosPrintf(AIL_TEXT("defined interactively by the user. The extracted blob's\n"));
MosPrintf(AIL_TEXT("features are drawn with subpixel accuracy in a zoomable\n"));
MosPrintf(AIL_TEXT("display.\n\n"));
// Run Interactivity Example.
InteractivityExample(AilSystem, AilDisplay);
// Free defaults.
MappFreeDefault(AilApplication, AilSystem, AilDisplay, M_NULL, M_NULL);
return 0;
}
//***************************************************************************
// Interactivity example.
// Source image file specification.
#define IMAGE_FILE M_IMAGE_PATH AIL_TEXT("Seals.mim")
// Threshold for image binarization.
#define IMAGE_THRESHOLD_VALUE 110L
// Initial region parameters.
#define RECTANGLE_POSITION_X 160
#define RECTANGLE_POSITION_Y 310
#define RECTANGLE_WIDTH 200
#define RECTANGLE_HEIGHT 175
#define RECTANGLE_ANGLE 0
// Interactivity parameters.
#define SELECTION_RADIUS 10
// Value of enter key in Ascii table
#define ASCII_ENTER 13
void InteractivityExample(AIL_ID AilSystem, AIL_ID AilDisplay)
{
AIL_ID AilImage, // Image buffer identifier.
AilGraphicsList, // Graphics list identifier.
AilGraphicsContext, // Graphics context identifier.
AilBinImage, // Binary image buffer identifier.
AilBlobContext, // Context identifier.
AilBlobResult; // Blob result buffer identifier.
AIL_INT SizeX, // Size X of the source buffer.
SizeY, // Size Y of the source buffer.
RegionLabel; // Label value of the region.
STestParameters DataStructure; // Hook function data structure.
// Restore the source image.
MbufRestore(IMAGE_FILE, AilSystem, &AilImage);
// Display the buffer.
MdispSelect(AilDisplay, AilImage);
// Allocate a graphics list to hold the subpixel annotations.
MgraAllocList(AilSystem, M_DEFAULT, &AilGraphicsList);
// Increase the selection radius for easier interactivity.
MgraControlList(AilGraphicsList, M_LIST, M_DEFAULT, M_SELECTION_RADIUS,
SELECTION_RADIUS);
// Associate the graphics list to the display for annotations.
MdispControl(AilDisplay, M_ASSOCIATED_GRAPHIC_LIST_ID, AilGraphicsList);
// Allocate a graphics context for the draw operations.
MgraAlloc(AilSystem, &AilGraphicsContext);
// Enable the interactive mode.
MdispControl(AilDisplay, M_GRAPHIC_LIST_INTERACTIVE, M_ENABLE);
// Enable the use of action keys
MgraControlList(AilGraphicsList, M_LIST, M_DEFAULT, M_ACTION_KEYS, M_ENABLE);
// Add a selectable rectangular region.
MgraRectAngle(AilGraphicsContext, AilGraphicsList, RECTANGLE_POSITION_X,
RECTANGLE_POSITION_Y, RECTANGLE_WIDTH, RECTANGLE_HEIGHT, RECTANGLE_ANGLE,
M_CENTER_AND_DIMENSION);
// Retrieve the label of the rectangle graphic.
MgraInquireList(AilGraphicsList, M_LIST, M_DEFAULT, M_LAST_LABEL, &RegionLabel);
// Modify the line thickness of the rectangle.
MgraControlList(AilGraphicsList, M_GRAPHIC_LABEL(RegionLabel), M_DEFAULT, M_LINE_THICKNESS, 5.0);
// Disable the selectable mode for the next annotations to the graphics list.
MgraControl(AilGraphicsContext, M_SELECTABLE, M_DISABLE);
// Allocate a binary image buffer for fast processing.
MbufInquire(AilImage, M_SIZE_X, &SizeX);
MbufInquire(AilImage, M_SIZE_Y, &SizeY);
MbufAlloc2d(AilSystem, SizeX, SizeY, 1+M_UNSIGNED, M_IMAGE+M_PROC, &AilBinImage);
// Binarize the source image.
MimBinarize(AilImage, AilBinImage, M_FIXED+M_LESS, IMAGE_THRESHOLD_VALUE, M_NULL);
// Allocate a blob context and a blob result.
MblobAlloc(AilSystem, M_DEFAULT, M_DEFAULT, &AilBlobContext);
MblobAllocResult(AilSystem, M_DEFAULT, M_DEFAULT, &AilBlobResult);
// Select the blob features to calculate (Center Of Gravity and Box).
MblobControl(AilBlobContext, M_CENTER_OF_GRAVITY + M_BINARY, M_ENABLE);
MblobControl(AilBlobContext, M_BOX, M_ENABLE);
// Programmatically initialize the selected state of the rectangle region.
MgraControlList(AilGraphicsList, M_GRAPHIC_LABEL(RegionLabel), M_DEFAULT,
M_GRAPHIC_SELECTED, M_TRUE);
// Perform and display a first count of the number of objects
// within the initial region.
CountObjects(AilDisplay, AilGraphicsList, AilGraphicsContext, AilBinImage,
AilBlobContext, AilBlobResult);
// Initialize the hook data structure, then associate the hook function to
// the "M_GRAPHIC_MODIFIED" event. The hook function will be called
// with any region interaction by the user.
DataStructure.AilDisplay = AilDisplay;
DataStructure.AilGraphicsList = AilGraphicsList;
DataStructure.AilGraphicsContext = AilGraphicsContext;
DataStructure.AilBinImage = AilBinImage;
DataStructure.RegionLabel = RegionLabel;
DataStructure.AilBlobContext = AilBlobContext;
DataStructure.AilBlobResult = AilBlobResult;
MgraHookFunction(AilGraphicsList, M_GRAPHIC_MODIFIED, &HookHandler, &DataStructure);
MosPrintf(AIL_TEXT("You can try using your mouse or your keyboard to interactively\n"));
MosPrintf(AIL_TEXT("modify the displayed region, such as moving, resizing, or\n"));
MosPrintf(AIL_TEXT("rotating the region. If you do so, the results and annotations\n"));
MosPrintf(AIL_TEXT("will be immediately updated.\n\n"));
MosPrintf(AIL_TEXT("Press Enter to exit.\n"));
AIL_INT PressedKey = 0;
while(PressedKey != ASCII_ENTER)
PressedKey = MosGetch();
MgraHookFunction(AilGraphicsList, M_GRAPHIC_MODIFIED+M_UNHOOK,
&HookHandler, &DataStructure);
// Free all allocations.
MblobFree(AilBlobResult);
MblobFree(AilBlobContext);
MbufFree(AilBinImage);
MgraFree(AilGraphicsContext);
MgraFree(AilGraphicsList);
MbufFree(AilImage);
}
AIL_INT MFTYPE HookHandler(AIL_INT HookType, AIL_ID EventId, void* UserData)
{
STestParameters* pDataStructure = (STestParameters*)(UserData);
// Check that the modified graphic is the rectangular region.
AIL_INT ModifiedGraphicLabel;
MgraGetHookInfo(EventId, M_GRAPHIC_LABEL_VALUE, &ModifiedGraphicLabel);
if (ModifiedGraphicLabel == pDataStructure->RegionLabel)
{
// Count objects and draw the corresponding annotations.
CountObjects(pDataStructure->AilDisplay,
pDataStructure->AilGraphicsList,
pDataStructure->AilGraphicsContext,
pDataStructure->AilBinImage,
pDataStructure->AilBlobContext,
pDataStructure->AilBlobResult);
}
return M_NULL;
}
#define MAX_TEXT_SIZE 100
void CountObjects(AIL_ID AilDisplay, AIL_ID AilGraphicsList, AIL_ID AilGraphicsContext,
AIL_ID AilBinImage, AIL_ID AilBlobContext, AIL_ID AilBlobResult)
{
AIL_INT NumberOfBlobs,
NumberOfPrimitives,
Index;
AIL_TEXT_CHAR TextLabel[MAX_TEXT_SIZE];
// Disable the display update for better performance.
MdispControl(AilDisplay, M_UPDATE, M_DISABLE);
// Remove all elements from the graphics list, except the rectangle
// region primitive at index 0.
MgraInquireList(AilGraphicsList, M_LIST, M_DEFAULT, M_NUMBER_OF_GRAPHICS,
&NumberOfPrimitives);
for(Index = NumberOfPrimitives-1; Index > 0; Index--)
{
MgraControlList(AilGraphicsList, M_GRAPHIC_INDEX(Index), M_DEFAULT, M_DELETE,
M_DEFAULT);
}
// Set the input region. The blob analysis will be done
// from the (filled) interactive rectangle.
MbufSetRegion(AilBinImage, AilGraphicsList, M_DEFAULT,
M_RASTERIZE + M_FILL_REGION + M_USE_LINE_THICKNESS_1, M_DEFAULT);
// Calculate the blobs and their features.
MblobCalculate(AilBlobContext, AilBinImage, M_NULL, AilBlobResult);
// Get the total number of blobs.
MblobGetResult(AilBlobResult, M_GENERAL, M_NUMBER + M_TYPE_AIL_INT, &NumberOfBlobs);
// Set the input units to display unit for the count annotations.
MgraControl(AilGraphicsContext, M_INPUT_UNITS, M_DISPLAY);
MosSprintf(TextLabel, MAX_TEXT_SIZE, AIL_TEXT(" Number of blobs found: %2i "),
(int) NumberOfBlobs);
MgraControl(AilGraphicsContext, M_COLOR, M_COLOR_WHITE);
MgraText(AilGraphicsContext, AilGraphicsList, 10, 10, TextLabel);
// Restore the input units to pixel units for result annotations.
MgraControl(AilGraphicsContext, M_INPUT_UNITS, M_PIXEL);
// Draw blob center of gravity annotation.
MgraControl(AilGraphicsContext, M_LINE_THICKNESS, 3.0);
MgraControl(AilGraphicsContext, M_COLOR, M_COLOR_RED);
MblobDraw(AilGraphicsContext, AilBlobResult, AilGraphicsList, M_DRAW_CENTER_OF_GRAVITY,
M_INCLUDED_BLOBS, M_DEFAULT);
// Draw blob bounding box annotations.
MgraControl(AilGraphicsContext, M_COLOR, M_COLOR_GREEN);
MgraControl(AilGraphicsContext, M_LINE_THICKNESS, 1.0);
MblobDraw(AilGraphicsContext, AilBlobResult, AilGraphicsList, M_DRAW_BOX,
M_INCLUDED_BLOBS, M_DEFAULT);
// Enable the display to update the drawings.
MdispControl(AilDisplay, M_UPDATE, M_ENABLE);
}